Initial Postoperative Hemoglobin Values Are Independently Associated With One-Year Mortality in Patients Undergoing Double-Lung Transplantation Requiring Intraoperative Transfusion

Abstract

Objective: To evaluate the association of postoperative hemoglobin values and mortality in patients undergoing double- lung transplantation with intraoperative transfusion.

Design: Retrospective cohort study.

Setting: University hospital.

Participants: Adult patients who underwent double-lung transplantation at the authors' institution, with intraoperative transfusion of packed red blood cells between 2009 and 2015.

Interventions: None.

Measurements and main results: Intraoperative transfusion requirements and general characteristics of 554 patients were collected. A generalized additive model, controlling for postoperative hemoglobin levels, number of transfused units of packed red blood cells, perioperative change in hemoglobin levels, disease leading to lung transplantation, and postoperative extracorporeal membrane oxygenation, was created to predict one-year mortality. A postoperative hemoglobin level of 11.3 g/dL was calculated as an optimal cutoff point. The patients were stratified according to this level. The end -point was all-cause one-year mortality after double-lung transplantation, assessed using the Kaplan-Meier analysis with log-rank test. All-cause mortality of the 554 patients was 17%. Postoperatively, 171 patients (31%) were categorized as being below the cutoff point. Improved survival was observed in the group with higher postoperative hemoglobin values (p = 0.002).

Conclusion: Lower postoperative hemoglobin levels in double-lung transplantation recipients were associated with increased mortality during the first year after surgery. Confirmation of these findings in additional investigations could alter patient blood management for double-lung transplantation.

Keywords: lung transplantation; mortality; outcome; transfusion; transfusion target.